4 1 8 



NA TURE 



[March i, 1906 



the writer the other stations, including Sydney, Bris- 

 bane, and Wellington for personal equation. At 

 Southport connection was made with the observatories 

 at Sydney and Brisbane, and from Doubtless Bav with 

 Wellington. 



It was on September 29, 1903, that the first mutual 

 observations and clock exchange were had with 

 Sydney, and so this night may be considered as the 

 one when for the first time longitude from the west 

 clasped hands with longitude from the east, and the 

 first astronomical girdle of the world was completed. 



In making the comparison at Sydney between the 

 longitude brought from the cast with that from the 

 west, I have used fhe value of Prof. Albrecht for 

 the arc Greenwich-Potsdam oh. 52m. 16051s., and for 

 the arcs from Potsdam to Madras, via Teheran, 

 Bushire, Karachi, Bombay, and Bolaram, those of 

 Major Burrard, giving for the longitude of Madras 

 5h. 20m. 59.235s. 



As there has been no re-determination of the various 

 arcs from Madras to Australia, I- have adopted the 

 values given in the Australian report of Ellery, Todd 

 and Russell. 



Applying these latter to the longitude of Madras, we 

 get for the longitude of Sydney" 



10 04 49 

 The Canadian value is 10 04 49 

 Difference 



°'355±°-o8S 

 0-287 + 0-058 

 0-068 



equivalent for the latitude of Sydney to 84 feet. The 

 1S86 value for Sydney is loh. 04m. 49.54s. 

 The final values of the Canadian determinations 



Ottawa, December 30, 1905. 



Otto Klotz. 



THE KANGRA EARTHQUAKE OF 

 APRIL 4, 1905^ 

 A FTER a lapse of only eight years since the great 

 - r " 1 - earthquake of 1897, India suffered another calamity 

 of the same nature on April 4, 1905, less in violence 

 and extent, but more calamitous in its results, for it 

 claimed a death-roll of 20,000 souls. An interesting 

 preliminary account of this earthquake, by Mr. C. S. 

 Middlemiss, appears in the concluding part of vol. 

 xxxii. of the Records of the Geological Survey of 

 India, where the total area over which the shock was 

 felt is estimated at about 1,625,000 square miles, as 

 against 1,750,000 in 1897. The area over which the 

 shock was destructive is smaller in proportion than 

 these figures would suggest, for the isoseist corre- 

 sponding to 10 degrees of the Rossi-Forel scale in- 

 cludes only 200 square miles, and that corresponding 

 to 8 degrees of the same scale 2150 square miles, as 

 against 300 and 145,000 in 1897. In comparing these 

 NO. 1896, VOL. 73] 



figures an allowance must be made for the personal 

 equation, and it seems that, if Mr. Middlemiss 's 

 standard had been adopted in 1897, the former of 

 these figures would have been considerably increased 

 and the latter somewhat reduced. 



There were two centres of great violence, one near 

 Kangra and Dharmsala, where the tenth degree of the 

 Rossi-Forel scale was surpassed, the other in the 

 Dehra Dun, where the ninth degree was not reached. 

 Between these two the violence was much less, and 

 Mr. Middlemiss points out that the two districts of 

 greatest destruction lie, each, in an embayment of 

 the course of the great boundary fault of the Hima- 

 layas ; they are the only two irregularities in the 

 generally even sweep of the boundary of the Tertiaries 

 of the sub-Himalayan tract, and as the general effect 

 of the Tertiary, and post-Tertiary, folding and fold- 

 faulting has been to obliterate irregularities in the 

 outline of the mountain-foot, it is natural to suppose 

 that any marked irregularities still left may be in a 

 peculiar state of strain, especially liable to give rise 

 to geotectonic movements. Those w T hich took place 

 on April 4 last seem to have exhausted themselves 



Scale 1 inch —36 miles 



I Alluvium »£[ 



Sabaran****,! 

 Tertiary System 



jv/Z/j Old Himalayan Hocks 



The ovals indicate Isoselsmal No. 8 



Fig. 1. — Origin of the Kangra earthquake of April 4, 1905. 



underground, for no surface faults or changes of level 

 were detected. 



The nature of the shock seems to have differed 

 from that of 1897, when all accounts agreed in 

 describing it as simple, with only one marked maxi- 

 mum of violence. In 1904 there were, both in the 

 Kangra and Dehra Dun districts, two or three 

 distinct shocks, and we may mention that this is 

 reflected in the long-distance records of the shocks, 

 which indicate at least two distinct impulses, following 

 each other at an interval of a couple of minutes, 

 whereas in 1897 there was no indication of more than 

 a single impulse. The violence of the shock at its 

 greatest seems to have been a little less than in 1S97; 

 at Kangra Mr. Middlemiss's observations give the ac- 

 celeration of wave particle as about 13 feet per second 

 per second, the amplitude as 9.75 inches, and the period 

 as 1.57 seconds. The time of origin, as deduced from 

 local observations, is said to have been 6h. 9m. os. 

 Madras time, within a second or two of error ; the rate 

 of propagation was 1.95 to 1.98 miles per second as 

 between the origin and the seismograph stations at 

 Bombay, Calcutta, and Kodaikanal, but it must be 



